Transmitting apparatus for wireless telegraphy.



PATENTBD JUNE 13, 1905. J. A. FLEMING.

TRANSMITTING APPARATUS FOR WIRELESS TBLEGRAPHY.

APPLICATIDNEILED SEPT. 7. 1904.

2 SHEETS-SHEET l.

S ATTORNEYS PATENTED JUNE 13, 1905.

5. A. FLEMING.

TRANSMITTING APPARATUS FOR WIRELESS TELEGRAPHY.

APPLICATION FILED SEPT. 7, 1904.

2 SHEETS-SHEET 2.

Ev JOHN AFLEW, 1 w; "W

H\S HTTORN EYS Nirnn STATES Patented June 13, 1905.

ATENT Fries,

JOHN AMBROSE FLEMING, OF UNIVERSITY COLLEGE, LONDON, ENGLAND,

ASSIGNOR, BY MESNE ASSIGNMENTS, TO' h IAROONI WIRELESS TELE- GRAPH COMPANY OF AMERICA, A CORPORATION OF NEI/V JERSEY.

TRANSMITTING APPARATUS FOR WIRELESS TELEGRAPHY.

SPECIFICATION forming part of Letters Patent No. 792,014, dated June 13, 1905.

Application filed September 7, 1904. Serial No. 223,617.

'10 roll Hill 077D it may concern.-

Be it known that I, JOHN AMBRosn FLEM- ING, doctor of science, a subject of the King of Great Britain, residing at University Colloge, Gower street, London, England, have invented certain new and useful Improvements in the Transmitting Instruments for IVireless Telegraphy, of which the following is a specification.

In wireless telegraphy of the Hertzianwave type the signal is created by the intermittent electrical discharge of a condenser, and this discharge must take place between metal balls or rounded metal surfaces and must be very sudden. It is usual to employ metal balls for thesedischarger-surfaces, between which the spark takes place. The noise of this spark however is exceedingly distressing and in the case of very large sparks there is a continual wearing of the discharger-surfaces which alters their character and makes them less eflicient.

The object of my present invention is to produce, in connection with a transmitting apparatus, sparking terminals, one of which may be moved, relatively to the other, whereby successive portions of the terminal or terminals are presented to the sparking point,

and also ,to produce a practically noiseless discharger.

The improvements consist especially in combining the conducting-bodies, between which the spark-gap is formed, with means whereby either or both of the conductingbodies will be moved, so as to continually present fresh discharge-surfaces between the bodies. Any suitable connections may be employed for this purpose, and any desired form of sparking terminals may be used. In the drawings, I have shown two spark-balls. Obviously, however, any suitable forms of sparking terminals may be used, and either one or both may be moved relatively to the other. Theballs may also be replaced by any other suitable shapes, but I have shown and hereinafter describe balls or disks of iron or steel, or other refractory conductors which are kept in rotation by means of clockwork or electric or other motors so that the places between which the discharge is taking place are constantly being changed. I also make arrangements for replacing these surfaces where required. These surfaces may c0n sist of balls of iron or steel or iron disks either solid or hollow so that water may be made to circulate in the interior and keep them cool. These balls or disks are carried on shafts which in turn are borne on insulating surfaces or bearings and they are placed at a proper distance apart for the discharge taking place and arrangements are provided for regulating this distance. Preferably this is done by supporting each ball with its motor on a table pivoted about one edge such tables being tilted more or less by means of screws.

I find it advantageous to place these balls or disks kept in rotation in a closed chamber in which air or other gases can be compressed,

and in this manner if the walls of the inelosing chamber are sufliciently thick and rigid I prevent any external sound so that the discharge is practically noiseless. In this chamber there is a window of very thick glass which permits of the electric spark being inspected and I ascertain the length of this spark by placing a lens in front of the window and throwing an image of the spark upon a screen. From the focal length of the lens and its distance from the spark it is easy to calculate the scale of magnification and therefore from the length. of the image to ascertain the real length of the spark.

The balls or disks between which the discharge takes place are driven round at a slow pace by means of gearing, which in turn is driven by a small electromotor or clockwork. When electric motors are employed each ball or disk is preferably driven by its own motor and these motors are contained in the sound-proof chamber which also contains the discharger. As the contact-surfaces are continually being changed they wear more evenly and the kind of spark therefore required for the performance of Hertzian wave telegraphy is better preserved. If these balls or disks are hollow, water may be caused to circulate through them and so keep them cool. I find that a very great advantage is secured by using a short spark taken in compressed air inelosed in a strong iron reservoir, as the electric discharge can be made perfectly noiseless and the injurious ell'ects arising from this sound are also obviated. In order to make the contact between the revolving ball or disk and the external electrical generaterwhether it be by a transformer, induction-coil or any other meansI employ mercury-cups. The terminals of the electric supply-circuit can be connected to two metal cups which are insulated and contain mercury. The shaft carrying the ball or disk has also on it a thick copper disk partly immersed in the mercury in this cup so that the ball or disk has therefore to revolve and yet a good connection is kept up with the external circuit, or else I at tach mercury-cups to the shaft of the revolving balls and cause rods to dip into these cups connected with the external circuit. If the discharger is inelosed in an air-tight reservoir containing compressed air, then the rods or cables coming from the generator must pass air-tight through the sides of the reservoir by means of glands. The screws also serving to alter the distance of the balls or disks must in the same way pass air-tight through the sides of the reservoir.

Figure 1 is a longitudinal section and Fig. 2 a transverse section of the apparatus.

a is a cast-iron ball say about six inches in diameter, which is traversed by a copper shaft 1) having a hard-steel point I) on the bottom end, and the top end having in it a steel pin b entering the cup formed in the top of the ball. Each ball is supported upon a wooden bridge 0 on ebonite insulators c carrying a brass sole-plate c in which there is a recess for the steel point t to rest. The ball is sustained in an upright position in the following manner: (1 (Z are two stout wooden uprights which carry horizontal corrugated ebonite insulators (1. These ebonite insulators carry a transverse copper strip (Z having attached to it a copper pin (Z This copper pin has a longitudinal hole bored in it to receive the steel pin 5 and in. order to prevent metal-to-metal contact, a glass tube 7) is slipped over the pin 6 The cup in the top of the ball is then filled with mercury. In this manner the ball is connected electrically by a very good joint with the copper strip (Z which is the terminal of the instrument and yet the ball itself is free to revolve quite easily. The ball is driven round by an electric motor in the following way: On the lower end of the shaft 1) is fixed a worm-wheel which engages with a worm e on an insulated shaft 6 of ebonite. On the shaft 6 is a second worm-wheel driven by the worm e en the shaft of the motor 6. The whole arrangcment is carried upon a platform composed of two boards ff jointed together by hinges The upper board f can be tilted by a screwf, so that by tilting the two tables which carry the two halves respectively of the discharger the balls can be brought nearer to or moved away from one another so as to vary the sparkgap.

This apparatus is inelosed in a sheet-steel or cast-iron drum g sufficiently large to con tain the whole discharger conveniently, preferably constructed like a small cylindrical boiler. In this boiler there is a pair of glands or stuffing-boxes g through which the cables are brought air-tight to the cop 3G1 strip (Z and also two glands g for the cab es, conveying the current and driving the small motors e Stuffing-boxes g are also provided for the screws f. In this manner the balls can be driven round in an air-tight chamber into which air can be pumped under pressure. As the action of the electric spark is to combine together the oxygen and nitrogen of the air producing nitric acid, it is better to employ nitrogen instead of air. It is desirable therefore to provide the closed chamber with a pressure-gage g and a safetyvalve so that a stated pressure may not be exceeded. In this closed chamber or iron boiler there should also be a small peep-hole g closed with a stout glass plate to enable the spark to be inspected.

hat I claim is- 1. In a producer of electromagnetic waves, a pair of conducting-bodies, separated by a spark-gap, and a motor and connections for rotating one of said bodies, and for causing sparking at successive portions of said body, substantially as described.

2. In a producer of electromagnetic waves, a pair of conducting-bodies separated by a spark-gap, and a pair of motors and connections for moving the pair of bodies simultaneously and for causing sparking between successive portions of the two bodies, sub stantially as described.

3. In a producer of electromagnetic waves, a pair of conducting-bodies separated by a spark-gap, and a motor and connections for moving one of said bodies relatively to the other, and for causing sparking at successive portions of said body, substantially as de scribed.

4. In a producer of electromagnetic waves, a pair of conducting-bodies separated by a spark-gap, a motor and connections for moving one of said bodies relatively to the other, and for causing sparking at successive portions of said body, and means for adjusting the sparking distance'between the bodies. substantially as described.

5. In a producer of electromagnetic waves, a pair of comlucting-bodies separated by a spark-gap, and one of which is carried by a movable table, means for moving one of said bodies relatively to the other, and means for moving the table whereby the sparking distance between the bodies is adjusted, substantially as described.

6. In a producer of electromagnetic waves, a pair of conducting-bodies separated by a spark-gap, and one of which is rotatably carried by a movable table, means for rotating the body carried by the table, and means for independently moving the table, substantially as described 7. In a producer of electromagnetic waves, a pair of conducting-bodies separated by a spark-gap, and one of which is rotatably carried by a hinged table, means for rotating the body carried by the table, and. means for tilting said table, substantially as described.

8. In a producer of electromagnetic waves, a pair of rotatable conducting-bodies separated by a spark-gap, and each of which'is carried by a movable table, means for rotating both bodies and connections whereby each table may be separately moved, substantially as described.

9. In a producer of electromagnetic waves, a pair of conducting-bodies separated by a spark-gap and a motor and connections for moving one of said bodies relatively to the other substantially as described.

10. In a producer of electromagnetic waves, a pair of conducting-bodies separated by a spark-gap, a motor and connections for moving one of said bodies relatively to the other, and means for adjusting the sparking distance between the bodies, substantially as described.

11. In a producer of electromagnetic waves, a pair of conducting-bodies separated by a spark-gap and one of which is carried by a movable table, and a motor and connections, also carried by said table, for moving one of said bodies relatively to the other, substantially as described.

12. In a producer of electromagnetic waves, a pair of conducting-bodies separated by a spark-gap and one of which. is pivoted in a movable table, and a motor and connections, also carried by said table, for driving the pivoted body, substantially as described.

13. In a producer of electromagnetic waves, a rotatable conducting-body provided with a cup, a pivot within said cup, a pivot at the lower end of the body, and means for driving said body, substantially as described.

1 1. In a producer of electromagnetic waves, a rotatable conducting-body provided with a cup, a pivot within said cup, an insulating-cap upon said pivot, a pivot at the lower end of the body, and means for driving said body, substantially as described.

between said body and a conductor, substantially as described.

16. In a producer of electromagnetic waves, a casing, means for supplying and maintaining fluid under pressure therein, sparking terminals within the casing and surrounded by the fluid, and a motor and connections for causing sparking at successive portions of the terminals, substantially as described.

17. In a producer of electromagnetic waves, a casing, sparking terminals, within the casing and surrounded by the fluid, a motor and connections for causing sparking at successive portions of the terminals, and conductors passing through stufling-boxes in the walls of the casing, substantially as described.

18. In a producer of electromagnetic waves, an insulated casing, conductors pass ing through the walls of the casing, sparking terminals within the casing, and one of which is movable relatively to the other, and means within the casing, for driving the movable terminal, substantially as described.

19. In a producer of electromagnetic waves, an insulated casing, conductors passing through the walls of the casing, sparking terminals within the casing, and one of which is rotatable, and means within the casing for rotating said terminal, substantially as described.

20. In a producer of electromagnetic waves, an insulated casing, a movable sparkterminal within the casing, and means for driving the movable terminal, substantially as described.

21. In a producer of electromagnetic waves, an insulated casing, a pivoted frame located within the casing, a spark-terminal carried by said frame, and means, extending through the casing for moving the frame and thereby adjusting the width of the spark gap, substantially as described.

22. In a producer of electromagnetic waves, an insulated casing, spark-terminals within the casing, one of said terminals being movable, a motor and connections within the casing, for moving the last-named terminal, and means, extending outside of the casing, for adjusting the sparking distance between the inclosed terminals, substantially as de scribed.

23. In a producer of electromagnetic waves, an insulated casing, a movable sparkterminal within the casing, and carried by a frame also located therein, a motor and conneetions carried by the frame, for driving said spark-terminal, and means, extending outside of the casing, for moving the frame, aforesaid, substantially as described.

24. In a producer of electromagnetic Waves, sparking terminals, and a motor and connections for causing sparking at successive portions of the terminals, substantially as described.

25. In a producer of electromagnetic Waves, a sparking terminal and a motor and CODIIGCtiODS for presenting successive portions of the terminal to the sparking point, substantially as described.

26. In a producer of electromagnetic Waves, a pair of sparking terminals and. means for causing sparking between successive portions of the terminals While maintaining the Width of the spark-gap practically constant, substantially as described.

27. In a producer of electromagnetic Waves, a pair of sparking terminals and means for moving one of said terminals While maintaining the Width of the spark-gap practically constant, substantially as described. 28. In a producer of electromagnetic Waves, a pair of spark-terminals, and means for moving bothv of said terminals While maintaining the Width of the spark-gap practically constant, substantially as described. 29. In a producer of electromagnetic Waves, a spark-terminal rotatably mounted upon an axis passing through said. terminal,

and means for rotating said terminal upon the aforesaid axis, substantially as described.

30. In a producer of electromagnetic Waves, a movable spark-terminal, and an electric motor and connections for moving said terminal, substantially as described.

31. In a producer of electromagnetic Waves, a closed casing, and a movable sparkterminal Within the casing, and means, also Within the casing, for moving said terminal, substantially as described.

32. In a producer of electromagnetic Waves, a spark-terminal, means for moving the same to present successive portions thereof for sparking, and means for independently moving said terminal to vary the Width of the spark-gap, substantially as described.

33. In a producer of electromagnetic Waves, a pair of movable frames, rotatable spark-terminals carried by said. frames, motors, one on. each frame, for driving the spark-terminals, and adjusting means for moving either of the frames, substai'itially as described.

JOHN AMBROSE FLEMING.

IVitnesscs:

JAMES EDWARD ToWnLL, Roenn'r FRANK IViLLi'AMs. 

